10.
Did you know?!?!
Another
name for
an
Extrusive
rock is a
VOLCANIC
rock

11.
A Closer Look at an Igneous
Rock
Obsidian is a dark-colored volcanic glass that forms from the very rapid
cooling of molten rock material. It cools so rapidly that crystals do not form.
Is it fine-grained or
coarse-grained?
Is this rock Intrusive
or Extrusive?

12.
http://www.youtube.com/watch?v
=PqgHUPSTojY
Must write down TWO things you
learned!!!!
Be prepared to share!